#2 Philadelphia lack many shooters
They rely too heavily on JJ Reddick's shooting. This was a known fact from even before this season started, that Philadelphia would lack consistent shooters from deep. We all hoped that Big Ben would somehow magically develop into a respectable shooter, or Markelle Fultz would truly announce himself in the NBA after a forgettable first year in the league.
Neither of those things has happened and now Philly are left to rely too much on JJ's shooting, although he has performed pretty well this season with an average of 18.7 points on 45% FG and 37% from behind the arc.
This becomes very evident when in the final minutes all opposition teams start to mark Reddick well and they are left with no space to create any good looks - so instead take poor shots and often find themselves losing close games.
So, Philadelphia need to handle their shooting woes otherwise they will be in deep trouble come playoff time - when defences will clog their offense and provide them no space to create better looks than they have been getting at times this season.